net/irda: Hold port lock while bumping blocked_open

Although tty_lock() already protects concurrent update to
blocked_open, that fails to meet the separation-of-concerns between
tty_port and tty.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 2 deletions

diff --git a/net/irda/ircomm/ircomm_tty.c b/net/irda/ircomm/ircomm_tty.c
index 1721dc7e4315..d282bbea710e 100644
--- a/net/irda/ircomm/ircomm_tty.c
+++ b/net/irda/ircomm/ircomm_tty.c
@@ -317,8 +317,8 @@ static int ircomm_tty_block_til_ready(struct ircomm_tty_cb *self,
         spin_lock_irqsave(&port->lock, flags);
         if (!tty_hung_up_p(filp))
                 port->count--;
-        spin_unlock_irqrestore(&port->lock, flags);
         port->blocked_open++;
+        spin_unlock_irqrestore(&port->lock, flags);
 
         while (1) {
                 if (tty->termios.c_cflag & CBAUD)
@@ -362,8 +362,8 @@ static int ircomm_tty_block_til_ready(struct ircomm_tty_cb *self,
         spin_lock_irqsave(&port->lock, flags);
         if (!tty_hung_up_p(filp))
                 port->count++;
-        spin_unlock_irqrestore(&port->lock, flags);
         port->blocked_open--;
+        spin_unlock_irqrestore(&port->lock, flags);
 
         IRDA_DEBUG(1, "%s(%d):block_til_ready after blocking on %s open_count=%d\n",
               __FILE__, __LINE__, tty->driver->name, port->count);